Boxed header for air-cooled heat exchanger

Abstract

A boxed header is formed from an exterior side plate, an interior side plate, a top plate, a bottom plate, a first end plate and a second end plate. The top plate is connected to the exterior side plate and the interior side plate with welded joints that are formed at the juncture between J-beveled top edges on the exterior side plate and the interior side plate that support the weight of the top plate during assembly. Once the top plate has been secured, the boxed header can be rotated and the bottom plate is attached to the exterior side plate and the interior side plate with welded joints that are formed at the juncture between J-beveled bottom edges on the exterior side plate and the interior side plate that support the weight of the bottom plate during assembly.

It is claimed: 
     
       1. A method for making a boxed header, the method comprising the steps of: providing an exterior side plate that has a top side, a bottom side and a length, wherein the top side and bottom side of the exterior side plate each includes a J-beveled edge extending along the length of the exterior side plate, wherein each J-beveled edge includes a horizontal landing ledge and an upright face; providing an interior side plate opposite to the exterior side plate, wherein the interior side plate has a top side, a bottom side and a length, and wherein the top side and bottom side of the interior side plate each includes a J-beveled edge extending along the length of the interior side plate, wherein each J-beveled edge includes a horizontal landing ledge and an upright face; providing a top plate having a V-beveled exterior side edge and a V-beveled interior side edge; positioning the top plate between the exterior side plate and the interior side plate such that an underside of the V-beveled exterior side edge of the top plate rests on the horizontal landing ledge of the J-beveled edge of the top side of the exterior side plate resulting in formation of a first closed root joint at an intersection of the top plate with the top side of the exterior side plate and an underside of the V-beveled interior side edge of the top plate rests on the horizontal landing ledge of the J-beveled edge of the top side of the interior side plate resulting in formation of a second closed root joint at an intersection of the top plate with the top side of the interior side plate; said first closed root joint being spaced from the upright face of the J-beveled edge of the top side of the exterior side plate so that the first closed root joint has a first reduced cross-sectional area and said second closed root joint being spaced from the upright face of the J-beveled edge of the top side of the interior side plate so that the second closed root joint has a second reduced cross-sectional area; positioning a welding probe between the V-beveled exterior side edge of the top plate and the upright face of the J-beveled edge of the top side of the exterior side plate in functional proximity to the first closed root joint; welding the top plate to the exterior side plate including making a first root pass weld with the welding probe along the length of the exterior side plate so that partial penetration of the first closed root joint is created through the first reduced cross-sectional positioning a welding probe between the V-beveled interior side edge of the top plate and the upright face of the J-beveled edge of the top side of the interior side plate in functional proximity to the second closed root joint; welding the top plate to the interior side plate including making a second root pass weld with the welding probe along the length of the interior side plate so that partial penetration of the second closed root joint is created through the second reduced cross-sectional area. 
     
     
       2. The method of  claim 1 , wherein the step of welding the top plate to the interior side plate further comprises the steps of: positioning the welding probe outside the boxed header in functional proximity to the second root pass weld; making one or more filler pass welds between the top plate and the J-beveled edge of the top side of the interior side plate; positioning the welding probe inside the boxed header in functional proximity to both the top plate and the interior side plate; and making an internal pass weld with the welding probe along substantially the entire length of the interior side plate. 
     
     
       3. The method of  claim 1 , wherein the step of welding the top plate to the exterior side plate further comprises the step of: positioning the welding probe outside the boxed header in functional proximity to the first root pass weld; and making one or more filler pass welds between the top plate and the J-beveled edge of the top side of the exterior side plate. 
     
     
       4. The method of  claim 3 , wherein the step of welding the top plate to the exterior side plate further comprises the steps of:
 positioning the welding probe inside the boxed header in functional proximity to both the top plate and the exterior side plate; and 
 making an internal pass weld with the welding probe along substantially the entire length of the exterior side plate. 
 
     
     
       5. The method of  claim 1 , further comprising the steps of:
 rotating the exterior side plate, interior side plate and top plate to orient the top plate below the horizontal landing ledges of the top sides of the exterior side plate and interior side plate; 
 positioning a bottom plate between the exterior side plate and the interior side plate such that the bottom plate rests on the J-beveled edges of the bottom side of the exterior side plate and the bottom side of the interior side plate; 
 welding the bottom plate to the exterior side plate; and 
 welding the bottom plate to the interior side plate. 
 
     
     
       6. The method of  claim 5 , wherein the step of welding the bottom plate to the interior side plate further comprises the steps of: positioning the welding probe outside the boxed header in functional proximity to both the bottom plate and the horizontal landing ledge of the bottom side of the interior side plate; making a third root pass weld with the welding probe along substantially the entire length of the interior side plate; positioning the welding probe outside the boxed header in functional proximity to the root pass weld; making one or more filler pass welds between the bottom plate and the J-beveled edge of the bottom side of the interior side plate; positioning the welding probe inside the boxed header in functional proximity to both the bottom plate and the interior side plate; and making an internal pass weld with the welding probe along substantially the entire length of the interior side plate. 
     
     
       7. The method of  claim 5 , wherein the step of welding the bottom plate to the exterior side plate further comprises the steps of: positioning the welding probe outside the boxed header in functional proximity to both the bottom plate and the horizontal landing ledge of the bottom side of the exterior side plate; making a fourth root pass weld with the welding probe along substantially the entire length of the exterior side plate; positioning the welding probe outside the boxed header in functional proximity to the root pass weld; making one or more filler pass welds between the bottom plate and the J-beveled edge of the bottom of the exterior side plate; positioning the welding probe inside the boxed header in functional proximity to both the bottom plate and the exterior side plate; and making an internal pass weld with the welding probe along substantially the entire length of the exterior side plate. 
     
     
       8. The method of  claim 5 , further comprising the steps of:
 positioning a first end plate between the exterior side plate, interior side plate, top plate and bottom plate; and 
 welding the first end plate to the exterior side plate, interior side plate, top plate and bottom plate. 
 
     
     
       9. The method of  claim 8 , further comprising the steps of:
 positioning a second end plate between the exterior side plate, interior side plate, top plate and bottom plate; and 
 welding the second end plate to the exterior side plate, interior side plate, top plate and bottom plate.